Having used the 50mm as a walk-around lens in cities I say it gives interesting perspectives but limits you because of the narrow field of view. I would assume the 35mm gives more freedom without having to step too much back or have to switch lenses.

Currently calibrating 52 test-shots for white-balance and brightness. Two things are obvious so far:
- the 35/1.4G reproduces the strongest reds
- the 35/1.8G often needs around +0.5EV exposure compensation in post to match the brightness of the other two 35mm lenses.
I'm currently looking deeper into this issue to make sure this is not the fault of the aperture lever.

-------almost seven hours later-------
Some things simply wont go away...
When looking a bit deeper into the case of the vanishing light I made sure first, that the aperture lever was working correctly and the aperture on each lens stayed indeed wide open, when the aperture was set to max. Then I shot a series under constant light with fixed shutter speed, stopping down to f/11 in single stops.
I found that the 35/1.8G made indeed the expected -1EV steps until I stopped down from f/5.6 to f/8, where it darkened almost -1.5EV followed by another -1.7EV (!) when stopping to f/11.
The 35/1.4G behaved well until f/8 and darkened -1.5EV when stopping down to f/11. The 35/2.0D darkened -1.2EV from f/8 to f/11 but behaved pretty well otherwise. On the bright side (i.e. when opening from the second largest aperture to the largest) the 35/2.0D underperformed with only +0.8EV brightening when opening from f/2.8 to f/2.0 (measured in the middle of the image - so there's no influence from vignetting) while the 35/1.4G overperformed with +1.2EV (albeit with pretty heavy vignetting) when going from f/2.0 to f/1.4. Btw. the 35/1.8G just performed as expected: It brightened +1/3EV when going form f/2.0 to f/1.8.
Hmm...
So in principle the apertures seem to be working as expected at least above f/8. And I assume the funny results with smaller apertures is simply the diminishing precision of the aperture mechanism.
Then I went to the cross-lens-comparison and had a look at the "safe" apertures from 1 stop below max down to f/5.6 or f/8.0. And my earlier results were confirmed: The 35/1.8G was indeed -0.5EV darker on average than the 35/1.4G. If you think that this higher transmission of Nikon's latest and greatest 35mm prime is due to nano-coating, think again: The old 35/2.0D in turn was even another 0.25 brighter than the 35/1.4G!

To sum it all up: The 35/1.4G has on average a 0.5EV higher transmission than the 35/1.8G and it serves almost +1.35EV more light when fully opened.
That was something I did not expect.

I'd like to hear your take on my findings, please!
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Oh I forgot: all processing was set to standard (camera profile), no lens profiles used, with linear (!) contrast curve.